1. Field of the Invention
This inventions relates to a vehicle seat back recliner for permitting tilting adjustment of a seat back with respect to an associated seat cushion of a vehicle seat.
2. Background Art
Vehicle seat back recliners of the “rotary” type conventionally include a stationary member mounted on the associated seat cushion and a pivotal member that is mounted for pivotal movement about a pivotal axis on the stationary member to mount a seat back. A locking mechanism controls the adjusted position of the pivotal member on the stationary member to control the tilted orientation of the seat back. Such recliners can position the seat back generally upright for normal seating, rearwardly for reclined seating, forwardly for access to the rear of the seat or horizontally in a forward direction for cargo usage.
Conventional locking mechanisms of the rotary type of seat back recliners include a toothed locking ring on the pivotal member and a plurality of pawls mounted on the stationary member for movement between locking and unlocked positions with respect to the toothed ring under the control of a single cam that rotates around the pivotal axis of the recliner and has cam lobes engaging each of the pawls. With such a construction, full locking engagement of one of the toothed pawls with the toothed locking ring can prevent farther cam movement and complete locking of each other pawl.
Prior vehicle seat back recliners noted during an investigation conducted in connection with the present application include: U.S. Pat. No. 4,770,464 Pipon et al.; U.S. Pat. No. 5,216,936 Baloche; U.S. Pat. No. 6,102,480 Asano; U.S. Pat. No. 6,260,923 Yamada et al.; U.S. Pat. No. 6,328,382 Yamashita; and U.S. Pat. No. 6,454,354 Vossmann et al.; and also include Japanese Patent Publication 1-104201.